Failover Cluster Instance Administration and Maintenance

Applies to: SQL Server

Maintenance tasks like adding or removing nodes from an existing Always On Failover Cluster Instance (FCI) are accomplished using the SQL Server Setup program. Other administration tasks like changing the IP address resource, recovering from certain FCI scenarios are accomplished using the Failover Cluster Manager snap-in, which is the management snap-in for the Windows Server Failover Clustering (WSFC) service.

Maintaining a Failover Cluster Instance

After you have installed an FCI, you can change or repair it using the SQL Server Setup program. For example, you can add additional nodes to an FCI, run an FCI as a stand-alone instance, or remove a node from a FCI configuration.

Adding a Node to an Existing Failover Cluster Instance

SQL Server Setup gives you the option of maintaining an existing FCI. If you choose this option, you can add other nodes to your FCI by running SQL Server Setup on the computer that you want to add to the FCI. For more information, see Create a New SQL Server Failover Cluster (Setup) and Add or Remove Nodes in a SQL Server Failover Cluster (Setup).

Removing a Node from an Existing Failover Cluster Instance

You can remove a node from an FCI by running SQL Server Setup on the computer that you want to remove from the FCI. Each node in an FCI is considered a peer without dependencies on other nodes on the FCI, and you can remove any node. A damaged node does not have to be available to be removed, and the removal process does not uninstall the SQL Server binaries from the unavailable node. A removed node can be added back to a FCI at any time. For more information, see Add or Remove Nodes in a SQL Server Failover Cluster (Setup).

Changing Service Accounts

You should not change passwords for any of the SQL Server service accounts when an FCI node is down or offline. If you must do this, you must reset the password again by using SQL Server Configuration Manager when all nodes are back online.

If the service account for SQL Server is not an administrator in your cluster, the administrative shares cannot be deleted on any nodes of the cluster. The administrative shares must be available in a cluster for SQL Server to function.


Do not use the same account for the SQL Server service account and the WSFC service account. If the password changes for the WSFC service account, your SQL Server installation will fail.

On Windows Server 2008, service SIDs are used for SQL Server service accounts. For more information, see Configure Windows Service Accounts and Permissions.

Administering a Failover Cluster Instance

Task Description Topic Link
Describes how to add dependencies to a SQL Server resource. Add Dependencies to a SQL Server Resource
Kerberos is a network authentication protocol designed to provide strong authentication for client/server applications. Kerberos provides a foundation for interoperability and helps to enhance the security of enterprise-wide network authentication. You can use Kerberos authentication with SQL Server stand-alone instances or with Always On FCIs. Register a Service Principal Name for Kerberos Connections.
Provides links to content that describes how to enable Kerberos authentication
Describes the procedure used to recover from a SQL Server failover cluster failure. Recover from Failover Cluster Instance Failure
Describe the procedure used to change the IP address resource for a SQL Server failover cluster instance. Change the IP Address of a Failover Cluster Instance

See Also

Configure HealthCheckTimeout Property Settings
Configure FailureConditionLevel Property Settings
View and Read Failover Cluster Instance Diagnostics Log